The Mountain Hawks (5-0) trailed 14-0 midway through the first but rebounded and took a 31-21 lead before the Rams (3-2) evened the score in the fourth quarter.
Peery's kick extended Lehigh's regular season winning streak to 14, tops in the country.
Mike Colvin threw for a career-high 341 yards and a touchdown on 24-of-40 passing, and also rushed for 61 yards and a score. Ryan Spadola finished with eight catches for 85 yards.
Zach Barket and Keith Sherman rushed for touchdowns of 48 and 41 yards, respectively. The Mountain Hawks outrushed the Rams 174 yards to 69 and have won 14 of the past 15 against the Rams.
Fordham's Ryan Higgins was 28-for-41 passing for 373 yards and two touchdowns.